Terminal pin removing tool



Dec. 14, 1965 D. N. CAMARGO 3,222,766

TERMINAL PIN REMOVING TOOL Filed July 1, 1963 'IIII-Z'IIIIIIII INV EN TOR. Dav? 'cK/V'Camarga United States Patent 3,222,766 TERMHNAL PIN REMOVING TOOL David N. Camargo, Sylmar, Calif. Union Aircraft (10., 1106 W. Isabel St, Burbank, Calif.) Filed July 1, 1963, Ser. No. 291,781 2 Claims. (Cl. 29203) This invention relate-s to a pin removing tool and is more particularly concerned with a tool for removing terminal pins and posts in electrical equipment.

The use of terminal pins and posts in electrical equipment is old and well-established. In recent years it has become common practice, when terminal pins and posts are required, to provide bodies of dielectric or insulating material to support and carry the pins or posts. The pin supporting bodies are provided with through openings in which the pins or posts are engaged. Originally th pins and posts were press fitted into the openings in the body, but due to the tendency for such a connection to fail, various types of locking means have been developed. The most practical and widely-used means for retaining such pins or posts in their related openings in the carrier bodies have involved a stop flange in the opening in the body, a cooperating stop shoulder on the pin or post to engage one side of the flange and a snap ring or other like expansible element or part on the pin to engage the other side of the flange. In such structures, the snap ring or expansible part on the pin or post occurs within the opening in which the pin is engaged and is not accessible. As a result of this relationship of parts, it is frequently impossible to remove such pins or posts from their carrier bodies without damage to the bodies, or without the aid of especially constructed removal tools which can be inserted in the annulus normally occurring between the pin and the wall of the opening in which it is engaged and which will collapse or compress the snap ring or member, making it possible to remove the pin.

The prior art has provided several tools of the character referred to above, each of which includes a tubular stem-like part to slidably receive the pin and to slidably enter the opening in which the pin is engaged, so as to engage and compress or collapse the snap ring, and a plunger adapted to slidably enter the stem, when it is engaged about a terminal pin or post and to urge the pin from engagement in the stem and therefore from the carrier body in which the stem is engaged.

Due to the extremely small size of the ordinary terminal pin or post and due to the slight working clearance between the pin and the wall of the opening in which it is engaged, the tubular stems of terminal post removing tools of the character referred to are extremely small in diameter and have extremely thin walls and as a result are, in addition to being extremely difficult and costly to manufacture, extremely delicate and fragile. Accidental dropping of such tools on their stems, bumping the stems or biasing the stems when using the tools frequently results in destruction or damage of the stem and renders the tools useless.

An object of the present invention is to provide a terminal pin or post removing tool of the general character referred to wherein the tubular stem is supported and protected against damage, thereby providing a tool which is easy and more convenient to operate and use and which is more economical to maintain.

Another object of the present invention is to provide a tool of the general character referred to wherein the plunger normally occurs within and projects from the free end of the stem so as to protect the end of the stem and support the stem throughout its longitudinal extent.

Still another object of the present invention is to provide a tool of the character referred to wherein the plunger is spring loaded and is such that it can be readily displaced from within the stem by engagement of a terminal post or pin in the stem.

Yet another object of the present invention is to provide a tool of the character referred to, including means for urging the plunger into and through the stem to urge a pin engaged therein therefrom. I

It is an object of my invention to provide a tool of the character referred to which is easy and economical to manufacture which is rugged and durable and which is highly effective and dependable in operation.

The various objects and features of my invention will be fully understood from the following detailed description of a typical preferred form and application of my invention, throughout which description reference is made to the accompanying drawings, in which:

FIG. 1 is an elevational view of my new tool and of a typical terminal pin and carrier body assembly;

FIG. 2 is a sectional view taken as indicated by line 22 on FIG. 1;

FIG. 3 is a view similar to FIG. 2, and showing the construction in a different position;

FIG. 4 is a View similar to FIGS. 2 and 3 and showing the structure in yet another position;

FIG. 5 is an enlarged detailed sectional view of a portion of the structure shown in FIG. 2;

FIG. 6 is an enlarged detail sectional view of a portion of the structure shown in FIG. 3;

FIG. 7 is an enlarged detail sectional view of a portion of the structure shown in FIG. 4;

FIG. 8 is an enlarged sectional view taken as indicated by line 88 on FIG. 5; and

FIG. 9 is an enlarged sectional view taken as indicated by line 9-9 on FIG. 6.

The present invention has to do with a novel tool for removing or ejecting a terminal pin P from engagement in a terminal pin receiving opening in a carrier body B.

Throughout the drawings, I have illustrated one typical form of terminal pin P and carrier body B.

The pin P is an elongate cylindrical member having inner and outer portions 10 and 11, the outer portion 11 being larger in diametric extent than the inner portion and defining a longitudinally inwardly-disposed stop shoulder 12 intermediate the ends of the pin. The inner portion 10 is provided with an annular groove 13 spaced inwardly from the shoulder 12 and in which a snap ring 14 is engaged. The groove is equal in depth with the diametric extent of the stock from which the snap ring 14 is made. The snap ring 14 is a semi-circular member and is such that its normal, major or outside diametric extent is larger than the diametric extent of the inner portion 10 of the pin and is such that when it is compressed radially inwardly or circumferentially, in the groove 13 in the pin, its major or outside diametric extent is equal to the outside diameter of the inner portion of the pin.

The end portions 10 and 11 of the pin P can be provided with central bores or openings to receive lead lines and the like, or can be provided with any other suitable means to facilitate the establishment of an electrical connection therewith.

The body B that I provide is shown as a simple blocklike body of dielectric or insulating material having inner and outer surfaces 20 and 21, mounting pads 22 at opposite sides thereof and a plurality of terminal pin receiving openings 23 extending through the body from the inner to the outer surfaces thereof.

The mounting pads 22 are shown secured to a suitable wall or panel structure 24, by means of suitable fasteners 25.

The openings 23 correspond in diametric extent with the diameter of the larger outer portion 11 of the pins P and are provided at their outer ends with radially inwardly-projecting flanges 26. The flanges 26 are substantially equal in longitudinal extent with the distance between the stop shoulder 12 on the pin and the snap ring 14 and are equal in inside diametric extent with the diametric extent of the inner portions of the pins P.

In practice, the inner ends of the pins P are slidably engaged through the flanges 26 and into the openings 23 from the outer surface of the block B and until the snap rings engage the flange, whereupon suflicient pressure is exerted onto the pins to cause the snap rings to collapse or constrict. The pins P are then urged rearwardly until the snap rings pass the flanges and expand again to engage the inner sides or surfaces of the flanges and until the stop shoulders on the pins engage and stop against the outer sides or surfaces of the flanges.

When the pins P are engaged in the block B in the above manner, it will be apparent that they are locked in engagement therein with their stop shoulders and snap rings occurring at the opposite sides of the flanges 26.

The inner ends of the pins P terminate within the openings 23 in the bodies and are not accessible at the rear side of the body.

While it may be possible in certain installations to engage and remove a terminal pin P from the body, at the front side thereof, as by means of snip nose pliers, it is just as common that access can only be had to the pins from the rear side of the block, in which case an especially constructed removal tool, such as the tool that I provide, must be used.

It is to be understood that the pins P and body B illustrated and described above, are only typical of the general type of terminal pin and terminal pin carrying body construction which is widely used and that in practice the pins and/or the body can vary widely in details of construction without affecting the novelty of the present removal tool.

The tool provided by the present invention includes an elongate cylindrical body 30 having front and rear ends 31 and 32 and a straight, central, longitudinal bore 33, a tubular stem 34 carried by the body in axial alignment therewith and projecting overtly therefrom, an elongate plunger 35 slidably engaged in the stem to normally project from the opposite ends thereof, an elongate driver 36 slidably engaged in the body and engageable with the plunger to urge the plunger forwardly in the body, manually engag'eable operating means 37 slidably carried by the body and coupled with the driver and a compression spring 38 in the body between the plunger and the driver and normally yieldingly urging the plunger forwardly in the body and the stem and urging the driver rearwardly in the body.

The tubular stem is an elongate cylindrical member having front and rear portions 40 and 41. The rear portion 41 corresponds in outside diameter with the diameter of the bore in the body, is slidably engaged in the forward end of the bore and is locked in fixed position therein by a suitable set screw 42, carried by the body.

The front portion 40 of the stem is of reduced diameter, its outside diameter corresponding in diameter with the diameter of the opening 23 in the body B. Inside diameter of the stem corresponds in diameter with the outside diameter of the terminal pins P.

The plunger 35 is an elongate cylindrical member having a rear portion 43 corresponding in diameter with and slidably engaged in the bore 33 in the body 30 and a front portion 44 corresponding in diameter with the inside diameter of the stem. The front portion 44 of the plunger is slightly longer than the stem and is slidably engaged therein so that its rear portion 43 engages and stops against the rear end of the stem and its forward end projects a short distance beyond the front end of the stern.

With the above relationship of parts, it will be apparent that the plunger occurring within and projecting from the front end of the forward reduced portion of the stem supports the stem and protects its forward end.

The driver 36 is an elongate cylindrical member having a rear portion 45 slidably engaged in the bore of the body from the rear end thereof and a front portion 46 of reduced diameter projecting freely forwardly in the bore and having a flat front end to engage the rear end of the plunger.

The driver is shiftable longitudinally in the bore in the body from a normal rear position where the forward portion thereof is spaced from the plunger to an actuated or forward position where the front end of the front portion thereof engages the plunger, when the plunger is in its forward unactuated position.

The rear portion 45 projects from the rear end of the body and is coupled or connected with the operating means 37.

The operating means 37 includes an elongate sleeve 47 slidably engaged about the rear portion of the body to project rearwardly therefrom and is provided with a radially inwardly-projecting mounting flange 48 at its rear end, which flange engages and is fixed to the rear end of the driver 36.

The sleeve 47 is provided with an elongate longitudinally-extending slot opening 49 in its forward portion and in which the head of a retaining or keeper fastener 50, carried by the body, is engaged. The fastener 50 cooperates with the slotted sleeve to limit rearward shifting and displacement of the sleeve from the body.

The spring 38 that I provide is a simple, helical compression spring and is arranged in the bore in the body to occur between the plunger and the rear portion 45 of the driver and to occur about the forward portion 46 of the driver.

The spring 38 normally yieldingly urges the plunger forwardly in the body and the driver rearwardly in the body to their unactuated positions, as clearly illustrated in FIG. 2 of the drawings.

In operation, when it is desired to eject a terminal pin P from engagement in its related opening 23 in the carrier body B, the forward end of the plunger 35 is engaged on the inner end of the terminal pin in axial alignment therewith. The tool is then urged forwardly and so that the stem shifts forwardly relative to the plunger, which is stopped by the pin, and slidably enters the annulus between the pin and the Wall of the opening. Upon continued forward shifting of the stem, as by gripping the forward portion of the body 30 of the tool, the forward end of the stem is urged over the snap ring 14 and into flat butted engagement on the inner side of the flange 26 in the opening 23, as clearly illustrated in FIGS. 3 and 6 of the drawings.

When the stem is thus engaged about the inner portion of the pin, the snap ring and against the flange 26, the driver 36 is next urged forwardly by means of the operating means 37 to engage and urge the plunger forwardly in the stem and to thereby urge the inner portion of the pin P forwardly, out of the stem and from engagement in the opening 23, as clearly illustrated in FIGS. 4 and 7 of the drawings.

It will be apparent from the foregoing that the forward thin-walled portion of the stem 34 is supported at all times either by the forward portion of the plunger 35 or by the said forward portion of the plunger and the terminal pin engaged therein. As a result of the above combination and relationship of parts, the forward portion of the plunger is supported and protected against damage at all times.

Having described only a typical preferred form and application of my invention, I do not Wish to be limited or restricted to the specific details herein set forth, but wish to reserve to myself any modifications or variations that may appear to those skilled in the art and fall within the scope of the following claims:

Having described my invention, I claim:

1. A tool for removing a terminal pin engaged through an opening in a body having front and rear surfaces, said pin having a forwardly disposed stop shoulder engaging said front surface, an annular groove adjacent the rear surface and a snap ring normally partially engaged in said groove and engaging said rear surface, said tool including an elongate, manually engageable body with front and rear ends, an elongate forwardly opening tubular terminal pin and snap ring receiving stem projecting forwardly from the body, an elongate terminal pin engaging plunger shiftably carried by the body and slidably engaged through the stem, spring means carried by the body and engaging the plunger to normally yieldingly urge the plunger forwardly where it projects from the forward end of the stem, said plunger being adapted to be urged rearwardly in the stem and body by a terminal pin when said stem is urged forwardly into engagement about a terminal pin and about a snap ring related thereto, and a manually engageable driver shiftably carried by the body rearward of the plunger and adapted to be shifted forwardly relative to the body and into engagement with the plunger to shift the plunger forwardly in the stern and to urge a terminal pin and snap ring forwardly out of engagement in the stem and through an opening in a body with which said pin and snap ring are related, said spring means engaging the driver and normally yieldingly urging the driver rearwardly relative to the body.

2. A tool for removing a terminal pin engaged through an opening in a body having front and rear surfaces, said pin having a forwardly disposed stop shoulder engaging said front surface, an annular groove adjacent the rear surface and a snap ring normally partially engaged in said groove and engaging said rear surface, said tool including an elongate, manually engageable tubular body with front and rear ends, an elongate forwardly opening terminal pin and snap ring receiving tubular stem projecting forwardly from the forward end of the body, an elongate plunger having a rear portion arranged in the body to normally occur in the forward end thereof and a front terminal pin engaging portion slidably engaged in the stem to normally extend through and to the forward end of the stem, said plunger being adapted to be urged rearwardly in the stem and body by a terminal pin when said stem is urged forwardly into engagement about a terminal pin and about a snap ring related thereto, an elongate manually engageable driver slidably arranged in the body to normally occur in and project from the rear end portion thereof and shiftable forwardly in the body to engage the plunger, and a compression spring in the body between the rear portion of the plunger and the driver and normally yieldingly urging the plunger forwardly and the driver rearwardly.

References Cited by the Examiner UNITED STATES PATENTS 2,960,864 11/1960 Watts 73-141 3,074,155 1/ 1963 Cootes et al. 29206 3,075,283 1/ 1963 Jansch 29206 WHITMORE A. WILTZ, Primary Examiner.

THOMAS H. EAGER, Examiner. 

1. A TOOL FOR REMOVING A TERMINAL PIN ENGAGED THROUGH AN OPENING IN A BODY HAVING FRONT AND REAR SURFACES, SAID PIN HAVING A FORWARDLY DISPOSED STOP SHOULDER ENGAGING SAID FRONT SURFACE, AN ANNULAR GROOVE ADJACENT THE REAR SURFACE AND A SNAP RING NORMALLY PARTIALLY ENGAGED IN SAID GROOVE AND ENGAGING SAID REAR SURFACE, SAID TOOL INCLUDING AN ELONGATE, MANUALLY ENGAGEABLE BODY WITH FRONT AND REAR ENDS, AN ELONGATE FORWARDLY OPENING TUBULAR TERMINAL PIN AND SNAP RING RECEIVING STEM PROJECTING FORWARDLY FROM THE BODY, AN ELONGATE TERMINAL PIN ENGAGING PLUNGER SHIFTABLY CARRIED BY THE BODY AND SLIDABLY ENGAGED THROUGH THE STEM, SPRING MEANS CARRIED BY THE BODY AND ENGAGING THE PLUNGER TO NORMALLY YIELDINGLY URGE THE PLUNGER FORWARDLY WHERE IT PROJECTS FROM THE FORWARD END OF THE STEM, SAID PLUNGER BEING ADAPTED TO BE URGED REARWARDLY IN THE STEM AND BODY BY A TERMIANL PIN WHEN SAID STEM IS URGED FORWARDLY INTO ENGAGEMENT ABOUT A TERMINAL PIN AND ABOUT A SNAP RING RELATED THERETO, AND A MANUALLY ENGAGEABLE DRIVER SHIFTABLY CARRIED BY THE BODY REARWARD OF THE PLUNGER AND ADAPTED TO BE SHIFTED FORWARDLY RELATIVE TO THE BODY AND INTO ENGAGEMENT WITH THE PLUNGER TO SHIFT THE PLUNGER FORWARDLY IN THE STEM AND TO URGE A TERMINAL PIN AND SNAP RING FORWARDLY OUT OF ENGAGEMENT IN THE STEM AND THROUGH AN OPENING IN A BODY WITH WHICH SAID PIN AND SNAP RING ARE RELATED, SAID SPRING MEANS ENGAGING THE DRIVER AND NORMALLY YIELDINGLY URGING THE DRIVER REARWARDLY RELATIVE TO THE BODY. 